Process of extracting waxes from crude petroleum



Nov. 3, 1925.

E. PETTY PROCESS OF EXTRAGTING WAXES FROM vCRUDE PTROLEUM una sept. 15. 1921 2 Sheets-Sheet l ARES Nov. 3, 1925. 1,559,981 E. PETTY PROCESS 0F. EXTRAGTING'WAXES FROM CRUDE PETROLEUM Filed Sept. 15. 3921 2 Sheets-Sheet 2 Patented Nov. 3, i 1925.l

UNITED STATE-s PATENT oFFicE,

EARL PETTY, or WINFIELD, xANsAs, AssIeNon 'ro THE DE LAVAL sEPAnA'roaContl rANY, or NEW Yonx, N. Y., A conronA'rI'oN or NEW JERSEY.

PROCESS OF E.X'IRAYIING'v 'WAXFS ROM CRU'DE PETROLEUM.

,Appiiation med 'september 15, 1921. seriai'No. 506,755.

from Crude Petroleum, of whichthe fol.

lowing is a full, clear, and exact description, reference being had-tothe'accompany# ing drawings, which form a 'part of this specificatie In therefining of the crude oils known as paraffin base crude oils, it is customaryl to distill off successively products o f suc-f H described and claimed 1n. an applicati-on,

cessively higher boiling points, .such as naphtha, illuminating oil's, gas oils and wax distillates, leaving as a residue stock known as cylinder oil stock. The wax distillates carry in solution more or less wax or paraffin) of a crystalline form'. The cylinder oil stock contains more or less wax (or petrolatum) of an amorphous form.l The wax distillates and cylinder oil stock are subr jected to separate and different treatments to purify and decolorize and to separate out the wax content., Examples of such processes are set forth in applications for patents filed by me August 24, 1921, Serial Nos; 495,078, and 495,079.

The process embodying the present invention has for its object the simplification of known processes to produce crystalline wax, amorphous wax and various marketable products heretofore produced and to obtain'more nearly 'perfect results. The object is attained'by a newl order and arrangement off` sub-processes and4 more particularly by means 0f a different order and ar-` rangement of .the 'specific steps set forth in the patent applications above specified. D

The more speciiic object of my invention j is to obtain, from paraffin .base crudeniineral oil, wax mainly in amorphous formand wax mainly in crystalline form (paraiiin) practically free from oil. The process herein described embodying my lnvention 1nvolves treatment of. the oil before separating the waxes therefrom and the separation of these waxes, ina mixed or unresolved condition, and carrying Vcomparatively little oil, from the crudeA oil before distillation,

as well as the 'treatment of the waxes, after being so separated from the oil, to effect'.

their separation and toeliininate from the paraiin practically all' the oil that it vmay carry.

` It is therefore'nelcessa'ry tof describe herein the treatments to which the crude oil is subjected before the waxes are --separated Atherefrom as well as the treatments to which the waxes are subjected after such separation.v I have also herein described the treati i ments to which the crude oil-is subjected,

'after the removal of the waxes, for the pro-' ductionof various boiling point distillates and a low pour bright stock, although these last named treatments are no part of thel 4 present process, but form part of aprocess Serial No'. 650,782, led byme July 11, 1923. An understanding of the 'process may be more readily arrived at by describing the same in connection with the accompanying I first add to the crude oil enough naph-l tha to build the oil to a 42 B. the crude` oil supply and the naphtha supply being diagrammaticall the drawing. T e diluted stock is continuously transferred to a mechanical agitator c to which is continuously supplied a small amount of sulfuric acid from an acid tank ai.v The acid-treated oil is continuously pumped, with a' stream of water, from a reservoir e, of about one-tenth the volindicated at a and b `in ume o f the oil, into and through a pack of excelsior f and .thence into a De Laval een.-

pumped continuously to .a mechanical agitator 7L, to which is continuously supplied,

trifugal' oil Aseparator g, wherein the acid sludge and acid wash water vare 'separated 'from the oil. The oil from the separator is 95 from a tank ,-a stream of soda ash or caus-.

tic soda. From the. agitator k71 the' mixture,

--together with some wash water fromv areservoir y', is pumped through an excelsior pack k, wherein a more thorough emulsion '-is. effected, which emulsion continuousl outflows to another centrifugal separator L66 are sepa-rated from the neutralized oil.l The wherein the caustic sludge and vwash water mode. of operation of thegexcelsiorpacks l' specified, is set forthin an applicationl filed by me August 24, 1921, serial No. 495,080. The thus chemically treated and partially purified oil is continuously pumped into a mechanical mixin tank m, towhlch is continuously supplie from a supply n, a. Small proportion of fullers earth, which is intimately mixed with the oil. From the mixer m the oil owscontinuously into a preliminary purifier o, which is preferably a vacuum filter or a basketcentrifuge, wherein the bulk of the fullersearth and discoloring matter carried thereby are removed?" .The oil is then pumped into a De Laval centrifugal clarifier p wherein the oil is cbmpletely freed of the filter media and the remaining discoloring matter.

The thus chemically treated and filtered oil is thenreduced to a temperature sufficient to throw the wax out of' solution, Say to a temperature of about 20o F. This refrigeration maybe effected by running the'oil through a double pipe chiller 1' in heat eX- change relation with an oppositely flowing' outgoing stream-of cold Wax-free oil and thence through a tank o-r tanks s providedy with coils or shells containing refrigerated brine. The refrigerated mixture then runs into a centrifugal separator t, where the wax, being the heavier, isthrown to the periphery and the lighter o-il displaced inwardly; wax-free oil being discharged from the light liquid' outlet and wax carrying comparatively little oil from the heavy liquid outlet. The waX-free'oil is then brought' into heat exchange relation with the solution of oil and wax flowing toward the-separator, as above described.

The wax-free crude oil is now subjected to the usual distillation (say in still u) for reduction to naphtha, illuminating oils and gas oil see Fig. 2), leaving residue A. The distillation is then continued for reduction to low pour neutral oils (spindle, light, medium, heavy, red), la low pour residue B (see Fig. 2) remaining in the still.

Y This residue is diluted with naphtha and subjected to the same chemical andA decolorizing treatments as those to which the crude oil was subjected. This treatment will be rapid. The thus purified lubricating stock is placed in steam stills or vacuum stills and carefully distilled for recovery of naphtha and reduction to nished low pour bright stock (residue C, Fig. ,2). 7

In distilling the wax-free crude oil, as

above described, after the illuminating oil has been distilled off, leaving residiieA,

the distillation may be carried on, as above stated, to make as many separate diliz'erent gravity cuts as desired (for example, of spindle, light, medium, heavy, etc.) and each of these cuts may be diluted with naphtha and subjected to a chemical and filtration treatment as diagrammed in Fig. 2, essentially the same as. that which was applied to. the

crude stock but operating much more rapidly. Each distil ate is then reduced for separation and recovery of the naphtha. The distillation for drawing olf the naphtha is done preferably in vacuum stills at a very low temperature so that the color will not be impaired.`

The Wax ((carryin com aratively little` oil) separate from t e cru e-oil, as hereinbefore described, isWarmed vand then treated chemically and filtered-by essentially the same processV asv that described for treating the crude oil, as diagrammed in Fig. 3. The Wax is then heated to distill 0E and recover the naphtha. The temperature is then raised to distill ofi' the proportion of crystalline wax desired. The wax distillates resulting from the above treatment' corresponds in' character with the products known as wax distillates produced. by the usual process of fractional distillation of crude oil, except that the wax distillate produced by my process is much heavier in wax. Such wax distillate and the residue D (see Fig. 3) left in the still are then treated respectively as follows:

The wax distillate is treated in accordance vwith the process set forth in my application filed August l241, 1921. Serial No.' 495,079. This process comprises dilution with naphtha, treatment with sulfuric acid,

las desired.

The residue D left inthe wax still is alnorphous and can be reduced to whatever melting point is desired and then chemically treatedand filtered as desired.

In allthc foregoing steps, the apparatusfor -chemical treatment and filtration is closed and vapor proof and the loss from evaporation of 'the added naphtha would be small.

While I have herein specified the additions of naphtlia to the crude oil, it is desired to be understood that its addition is deemed unnecessary incase the specific gravity of the crude oil is as high as 42 B.

Having now fully described my invention, what I claim and desire tov protect by Letters Patent is 1. The process of treating paraflin base crude: mineral oil to obtain therefrom. wax

qll

mainly in amorphous form and wax mainly in crystalline form (paraflin), which oomprises' subjecting oil containing'said waxes to refrigeration and centrifugal separation .to separate wax from the oil, and subsein crystalline form (paraffin), which com-v prises subjecting oil containing said waxes to refrigeration and centrifugal separation to separate from the oil wax carrying comparatively little oil, subsequently distilling the wax to drive off a crystalline wax distillate containing comparatively little oil, and subjecting the crystalline Wax distillate to refrigeration and centrifugal treatment to eliminate from the crystalline wax substantially all the oil carried thereby.

3. The process of treating paralin base crude mineral oil to obtain therefrom wax mainly in amorphous form and waX mainly inl crystalline form (parailin), which comprises subjecting oil containing said waxesv to treatment with a mineral acid and an alkali, and to refrigeration and centrifugal separation to separate wax from the oil, and subsequently distilling the vwax to drive oil' a crystalline Wax distillate, leaving as a residue wax mainly in amorphous form.

4.-The process of treating paraiin base crude mineral oil to obtain therefrom wax mainly in amorphous form and wax mainly in crystalline'form (paraffin), which com* prises subjecting oil containing, saidwaxes to dilution with a light petroleum pr-oduct, to treatment with an acid and an alkali, treatment with afdecolorizing agent,` and to refrigeration and centrifugal separation to separate the wax from the oil, and subsequently distilling the wax to drive off a crystalline wax distillate, leaving as a residue wax mainly in thevamorphou's form.

The process of treating parafn base crude mineral oil to obtain therefrom wax mainly in amorphous form and wax mainly in crystalline form (parain), which comprises subjecting oil containing said waxes to refrigeration and centrifugal separation to separatevfrom the oil wax carrying comparatively little oil, subsequently distilling w the wax to drive -oif a crystalline Wax distillate containing comparatively little oil, and subjecting the crystalline Wax distillate to treatment with a mineral acid and an alkali and to refrigeration and centrifugal treatment toeliminate from the crystalline wax substantially' all the oil carried thereby.

6. The process of treating paraiin base crude mineral oil to obtain therefrom wax mainly in amorphous form and wagt mainly in crystalline form (paraffin), which comprises subjecting oil containing said waxes to refrigeration and centrifugal-separation to separate from the oil Wax carrying comparatively little oil, subsequently distilling the wax to drive olf a crystalline wax distillate containing comparatively little oil,

and subjecting the crystalline wax distillate to dilution with a light petroleum product, to treatment with a mineral acid and an alkali and to refrigeration and centrifu al treatment to eliminate from the crystalline lwax substantally all the oil carried thereby.v

7. The process of treating paralin `base crude mineral oil to obtain therefrom wax mainly in amorphous form and wax mainly in crystalline form (parafn), which comprises subjecting oil containing said waxes to refrigeration and centrifugal separation to separate wax from the oil, diluting the wax with a light petroleum product, treating the wax with a mineralv acid and an alkali, and distilling the diluted and chemically treated wax to drive off a er stalline wax distillate, leaving as a resi ue avax mainly in the amorphous form.

8. The pro ess of treating paraffin base crude mineral oilto obtain therefrom wax mainly in amorphous form and Wax mainly in crystalline form (paraflin), Awhich coniprises subjecting oil containing said waxes. to refrigeration and centrifugalseparation to separate from the oil wax carrying comparatively little oil, diluting the wax with a light petroleum product, treating the wax with a mineral acid and an'y alkali, distilling the diluted and chemically treated waxv to drive 0H a crystalline wax distillate containing comparatively little oil, and subjecting the crystalline wax distillatev to refri eration and centrifugal treatment to eliminate from the crystalline wax substantially all the oil'carried thereby.

9, The process of treating paralin base crude mineral oil to obtain therefrom wax mainly-,in amorphous form and wax mainly in crystalline form (paratlin), which comprises subjecting oil containing said waxes to refrigeration and centrifugal separation to separate from the oil wax carrying coniparatively little oil, diluting the-wax with a light petroleum product, treating the wax with a mineral acid and an alkali, distilling the diluted and chemically treated wax to drive 0H a crystalline wax distillate -containing comparatively little oil, diluting the crystalline wax distillate with a light petroleum product, treating with a mineral acid and an alkali, refrigerating, and centrifuging to eliminate from the crystalline wax substantially all the oil carried thereby.

l0. The process 'of treating paraflin base crude mineral oil to obtain therefrom wax to refrigeration and centrifugal separation to separate wax from the oil, and dlstllhng the Wax to drive off a crystalline Waxdistillate, leaving asa residue Wax mainly 1n the amorphous form.

11. The process of treating paraiiinbase crude mineral oil to obtain therefrom Wax mainly in amorphous form and wan mainly in crystalline form (paraffin), which cornprises subjecting the 011, before distlllatron, to refrigeration and centrlfugal separation to separate from the oil wax carryingcomparatively little oil, subsequently dlstillmg the Wax to drive off a crystalline Wax distillate containing comparatively little oil, and subjecting the crystalline Wax distillate to refrigeration and centrifugal treatment to eliminate from the crystalline Wax substantially all the oil carried thereby.

12. The process of treating paraflin base crude mineral oil to obtain therefrom Wax mainly in amor hous form and Wax mainly in crystalline orm (paraiin) which comprises subjecting the oil, before distillation, to treatment with a mineral acid and an alkali, and to refrigeration and centrifugal separa-tion to separate wax from the oil, and subsequently distilling the Wax to drive off a crystalline Wax distillate, .leaving as a residue mainly amorphous wax. l

13. The process of treating paraHin base crude mineral oil to obtain therefrom Wax mainly in amorphous 'form and Wax mainly in crystalline form (paraffin) Whichcom- `prises subjecting the-oil, before distillation, to dilution With a light petroleum product, to treatment With an acid and an alkali, treat-ment with a decolorizing agent, and to refrigeration and centrifugal separation to separate the Wai: from the oil, and subsequently distilling the wax to drive off a crystalline Wax distillate, leaving as a residue wax mainly in the amorphous form.

14. The process of'treating para'lin base crude mineral oil toobtain there om Wax mainly in amorphous form and wax mainly in crystalline forml (paraffin), which comprises subjecting the oil, before distillation, to refrigeration andcentrifugal sepa# ration to separate from the oil Wax carrying comparatively little oil, subsequently disfilling the 'wax to drive off a crystalline wax distillate containing comparatively little oil, and subjecting the crystalline Wax distillate to treatment With a mineral acid and au alkali and vto refrigeration and centrifugal treatment to eliminate from the crystalline wax substantially all the oil carried thereby. 15. The process of treating paraiin base. crude -mineral oil to obtain therefrom was:` mainly in amorphous form and Wax mainly in crystalline form (paraffin), which comprises subjecting the oil, before distillation, to refrigeration and centrifugal sepa- 'crude mineral oil to obtain therefrom Wax ration to separate from the oil wax carry- 65 .ing comparatively little oil, subsequently distilling the wax to drive off a crystalline AWax distillate containing comparatively trifugal treatment to eliminate from the crystalline wax substantially all the oil car- 4 ried thereby.

16. The process of.treating paraiiin base crude mineral oil to obtain therefrom Wax mainly in amorphous form and Wax mainly in crystalline form (paraiin), which comprises subjecting the oil, before distillation, to refrigeration and centrifugal separation to separate Wax' from the oil, diluting the Wax with a light petroleum product, treating the wax with a mineral acid and analkali, and distilling the diluted and chemically treated wax to driveroff a crystalline- Wax distillate, leaving as a residue 4Wax mainly inthe amorphous form.

17. The process of treating paraflin base mainly in amorphous form and Wax mainly in crystalline form (paraffin) which comprises subjecting the oil, before distillation, to refrigeration and centrifugal separation. to separate from the oil Wax carrying comparatively little oil, diluting the Waxwith a light petroleum product, treating the wax with a mineral acid and an alkali, distilling the diluted and chemically treated Wax to drive oft' a crystalline wax distillate con- 100 taining comparatively little oil, and subjecting the crystalline Wax distillate to refrigeration yand centrifugal treatment to eliminate from the crystalline Wax substantially all the oil carried thereby.

18. The. process of treating paraiin base crude mineral oil to obtain therefrom Wax mainly in amorphous form and Wax mainly in crystalline form (paraffin), which comprises subjecting the oil, before distillation, to refrigeration and centrifugal separation to separate from the oil Wax carrying comparatively little oil, diluting the Wax with a light petroleum product, treating the Wax with a mineral acid and an alkali, distilling the diluted and chemically treated Wax to drive o'l' a crystalline wax distillate containing comparatively little oil, diluting the -crystalline wax distillate with a light petroleum product, treating with. a mineral acid and an alkali, rcfrigerating, and centrifuging to eliminate from the crystalline wax substantially all the oil carried thereby.

In testimony of which invention, I have hereunto set myhand, at New York, on this 19th day of August, 1921.

EARL Pii'rrr 

